[jQuery] Autocomplete parm error

Hi,
I have provlem width autocomplete . I trying to give a extra Parm:
$().ready(function() {
    $("#sCity").autocomplete("http://my-ajax-page/", {
        width: 200,
        minChars: 4,
        extraParams:{province : $('#sLocId').attr('value')},
        selectFirst: false
    });
...//other code
});
I`m trying to autocomplete cities for selected province.
I will show it in example: http://screencast.com/t/5daqo8VTQCV
We heve two cities "Białystok" in two provinces(20 and 6).
When i chose one province and try search the city it work with old
parametr or it is the first call of page, the parametr is empty though
i chose province. Only when I reload page the city is correct.
Provinces inputs.
$('#map area').click(
    function()
    {
        var sLoc = $('#sLoc');
        sLoc.attr('value', $(this).attr('title'));
        $('#sLocId').attr('value',$(this).attr('alt'));
        $('#sCity').attr('value','');
        $('#sCityId').attr('value','');
        return false;
    }
);
sorry for my english ;)
Siner